Breathing circuits, also called anesthetic circuits, comprise a set of elements that allow gases and/or anesthetic vapors to be conducted from an anesthesia machine to a patient, so that a gas exchange with the exterior occurs. The function of the elements of the breathing circuit is not only to allow a proper administration of the anesthetic via the lungs but also provide oxygen and remove carbon dioxide in a suitable manner. Some of the elements of the breathing circuit are ringed or corrugated tubes, reservoir bags, overflow valves and/or directional valves, anesthesia machines, filters, connectors and oxygen masks among others elements.
Nowadays, when a patient undergoes a surgical procedure where the use of an anesthesia circuit is required, there is a risk that some of the elements of the circuit are disconnected, without the medical staff being aware of this situation, that results in a leakage of the anesthetic gas that does not cause immediate damage to the medical staff, nevertheless, if this situation repeatedly occurs it may cause serious damage to their health.
There are devices in the prior art that trigger an alarm in case of disconnection of an element to which they are attached, such as the device of Spanish patent application No. ES 0 444 404 A1, which comprises a pneumatic device that emits both a visual and an audible alarm when there is a disconnection of a tube previously inserted into another. In particular, the device is mainly focused on the disconnection of the tube that is directed to the endotracheal cannula of a breathing apparatus that allows the patient's breathing. To achieve this objective, said device comprises a pneumatic supply, a pneumatic switch, a filter, an adjustable decompressor, an “on-off”-type magnetic cell, which is fed by the power supply and is driven due to a pressure change in a capture tube, a distributor, an audio apparatus and a pneumo-electric switch. The capture tube should be inserted between the walls of the endotracheal cannula and the respiratory apparatus of the patient in order to operate the device. When there is a disconnection of the cannula, the tube that was previously pressurized, undergoes a pressure variation and a pressure decreasing which causes the pneumatic cell to tilt and the operative position of the distributor is initiated so that the activation of both audible and visual alarms happens.
However, since this device is pneumatic, the same has the disadvantage that requires a constant supply of air. Likewise, the pneumatic cell should be housed within a closed box to reduce noise that is caused by the exhausting of the gas during the operation of the device, which makes the device inconvenient for those patients that require the use of the same.
Another prior art example of elements that indicate leakage of anesthetic gas is that disclosed in U.S. Pat. No. 5,661,231 in which, it is revealed an arrangement for detecting filtrations or leaks in respiratory circuits by means of the use of a device designed for such purpose. Said device comprises two elements: a connector and a closure element. The connector has a “Y” form and is attached to the anesthesia machine that is part of the breathing circuit. The closure member has a cylindrical shape for allowing its insertion into the connector that is hollow inside. Also, the device comprises detection means on its outer surface that sends an electrical signal in case said two elements are decoupled. The detection means comprises, in turn, a button and a micro-switch located at the lower part of the button.
The operation of the above mentioned device is as follows: when the closure member is inserted into the connector, the button, which is located on the outer surface of the closure member, is pushed down in order to actuate the micro-switch. The micro-switch sends a signal to the anesthesia machine that constantly monitors said condition. If these elements are decoupled, the micro-switch is disabled so that the anesthesia machine emits an alarm signal indicating said decoupling.
One of the disadvantages of the device disclosed in US Patent '231, is that, all the time, an electrical connection should be present between the device and the anesthesia machine in order to emit the corresponding alarm. Since, a wired connection is permanently present between said two elements; there is a risk of inadvertent disconnection if the patient is moved. It is desirable that this type of device is provided with a portable power supply (battery) to achieve autonomy and provide greater comfort to patients and the medical staff. Also, another disadvantage of this device, is its possible incompatibility with other models of anesthesia machines of a given hospital.
In the medical field, and more specifically in the area of surgery, a major concern is intra-hospital contagious when using respiratory circuits including anesthesia machines, since some elements are reused. In order to eliminate this drawback, the invention of U.S. Pat. No. 3,556,097 is mainly based on the manufacture of the breathing circuit elements whose production costs are reduced and thus to be disposable leading to an improved hygiene in breathing circuits.
The above mentioned invention comprises a respiratory mask, collapsible conduits, an interconnecting device between the conduits and the breathing mask; a breathing bag and a filter. More particularly, the interconnecting device has a “T” form; so that at the lower end thereof it is coupled a breathing mask or an endotracheal cannula; while the lateral ends thereof are designed to connect foldable pipes, the device is characterized because there is a rotational movement between the device and the connected tubes, resulting in a greater comfort to the patient.
However, this patent document only mentions elements of the breathing circuit, but fails to mention any device or element which indicates to the patient or the medical staff if the components of the circuit are disconnected.
As it can observed from the above, in the prior art there is disclosed the use of interconnection devices to be coupled to respiratory or anesthesia circuits in order to facilitate its handling during surgery; however, these connecting devices of the prior art have the disadvantage that they do not include any element indicating to the medical staff if the breathing circuit is disconnected resulting in the leakage of anesthetic gas.
Consequently, it has been sought to overcome the drawbacks of the prior art by developing a multiple connector device for respiratory circuits with alarm due to disconnection.